Nortel DMS-100 Series General Description Manual page 37

Distinctive ringing is supported by the coded ringing, decimonic scheme at 20
Hz, and the REA frequency selective scheme at 30 Hz.
The following figures illustrate the relationship between the distinctive ringing
signals and the DMS-100 ringing cycle for the coded ringing and frequency
selective ringing schemes.
Figure 1-18 Distinctive ringing patterns - coded ringing scheme
1-party,1FR
2-party,ring
2-party,tip
4/8/10-party: Code1
Code 2
Code 3
Code 4
Code 5
Code 6
Code 7
Code 8
Ring side revertive ring
Tip side revertive ring
ANI/coin
Note 1: Coded 30 Hz ringing does not support 2/4/8/10 multiparty lines or
revertive ringing.
Note 2: Coded 20/30 Hz ringing for the LCM of the LCE frame/cabinet supports
2/4/8/10 multiparty lines with patterns shown in figure "LME/LCE coded ringing
patterns - immediate ring disabled" and the figure "LME/LCE coded ringing
patterns with immediate ring enabled." This can be accomplished using switch
settings for 20/30 Hz and a 2,2,1,1 cadence.
Note 3: Coded 30 Hz ringing for LMEs does not support 2/4/8/10 multiparty or
revertive ringing.
Note 4: Ring codes 2 and 6 have the same cadence but different timing, making
them very similar; therefore, do not assign these codes to the same line.
2 s
0 1 2
0 1 2
DMS-100 Family DMS-100 Ringing System BASE15 and up
DMS-100 ringing overview 1-21
6 s
0.5 s
2 s
3 4 5 6 7 8
3 4 5 6 7 8
1.5 s
9 10 11
9 10 11